This is my first mod I'm publishing to the community.
It's a small mod that allows 2 enchanted books with the same and one and only one enchantment to be combined in a crafting table to create a enchanted book with the same type of enchantment but one level higher.
I don't know if it already exists a mod like this one; I haven't seen one and haven't looked.
I made this because I always found it annoying to must enchant a weapon or tool with the books to be able to combine 2 low-level enchanting books I got using a MFR disenchanter. This problem is solved in 1.7 and later due to that you are then able to combine them in an anvil. But until then...
For now it's free to combine the books, but I may add a cost based on the value of the enchantment later.
Here is a video that mostly covers the whole mod:
It should work with enchantments from other mods as well so long as they have a book registered in the game.